Harrisburg (/ˈhærɪsbɜrɡ/ or /ˈhɛərzbərɡ/) is a city in and the county seat of Saline County, Illinois, United States. It is located about 57 miles (92 km) southwest of Evansville, Indiana, 111 miles (179 km) southeast of St. Louis, Missouri. The 2010 population was 9,017, and the surrounding Harrisburg Township had a population of 10,790, including the city residents.